1. Field of the Invention
This invention relates to word processing systems. More particularly, it relates to word processing systems wherein a plurality of display units share a single printer.
2. Description of the Prior Art
In the past decade word processing systems have rapidly assumed a position of great importance in the business equipment field. At the present stage, at a little more than the cost of a group of high quality typewriters, most business organizations can purchase a word processing system wherein the material to be produced is formatted on one or more display units each of which has a text formatting microprocessor, means such as a CRT for displaying the text and means for controlling a printer to print the finalized formatted text. Word processing systems strive for higher quality printed text produced more rapidly and efficiently than traditional means for producing printed text copy. The field is a highly competitive one with a great many companies marketing high quality efficient equipment. Because of the highly competitive nature of the field, cost reduction without sacrifice in quality has been a major goal in the field. Some typical word processing systems are described in U.S. Pat. Nos. 4,137,564, 4,126,893 and 4,138,719.
The present invention is directed towards such cost reduction in word processing systems wherein a plurality of display units share a single printer. Since about 65-95 percent of the time in producing a final hard copy is spent by the operator on the display unit in formatting the text to be involved in the hard copy and only 5-35 percent of the time spent in actual printing, the field has been moving in the direction of expedients whereby a plurality of display units are multiplexed, i.e., share a single printer.